Esters of (alkynloxy) and (alkenyloxy) carbanilic acid

ABSTRACT

The invention is novel esters of (alkynyloxy)-, (alkenyloxy)-, and (cyanoalkoxy) carbanilic acids and the thiono and dithio derivatives of the carbanilic acids, and their use for controlling broadleaf weeds and grasses.

Cross el al. Her. 3, R974 ESTERS 0F (ALKYNLOXY) AND [56] ReferencesCited (ALMIENYLOXY) CARBANILIC ACllll) UNITED STATES PATENTS [75]Inventors: lBarrington Cross, Rocky Hill; 3,721,699 3/1973 Traber et all260/471 C Robert Louis Arotin, Willingboro, both of PrimaryExaminerLorraine A. Weinberger [73] Assignee: American Cyanamid Company,Assistant f' Thaxton St f d Conn Attorney, Agent, or Firm-H. G. Jackson[22 Filed: June 30, 1972 [21] A l N 267 838 [57] ABSTRACT on Theinvention is novel esters of (alkynyloxyy, (alkenyloxy)-, and(cyanoalkoxy) carbanilic acids and 260/471 0 03, the thiono and dithioderivatives of the carbanilic 7l/10 1/l l 1, 260/455 A, acids, and theiruse for controlling broadleaf weeds 260/465 D, 260/470 and grasses. 51I 1. Cl. C07 125 06 n c 10 Claims, N0 Drawings Field of Search 260/471 CESTERS OF (ALKYNLOXY) AND (ALKENYLOXY) CARBANILIC ACID BACKGROUND OF THEINVENTION 1. Field of the Invention The invention pertainsto newchemical compounds and their use as herbicides.

2. DESCRIPTION OF THE PRIOR ART The literature is replete with examplesof herbicidal l carbanilic acid esters as herbicides. One of theearliest is CIPC, the isopropyl ester of m-chlo'rocarbanilic acid whichis a preemergence herbicide. Another is SWEP, the methyl ester of3,4-dichlorocarbanilic acid, a selective preemergence herbicide in rice.Our invention defurther Provided that when B CH2 T X is scribescarbanilates containing the hitherto undisclosed ygeni compPunds Q thewentlon are useful for alkynyloxy, alkenyloxy and cyanoalkyloxycarbanicomfollmg, 3 W val-let) of weeds lates- These compounds possessnot only good grasses. This utility involves the application of aherbiemergence activity but are equally effective .postemercdanyeffective amotmt of a compTund of thefabcve gence, yet possess importantcrop selectivity. A general f to (1 fohage or othef P am P i 0 un reviewof Carbanilate esters is Weeds 2 pg, 49, (1953) slrable plant species,or (2) to soul containing seeds of Further teachings are found in US.Pat. Nos. undeslrable plant specles 7 ,695,225 6,995 (19 DESCRIPTION OFTHE PREFERRED SUMMARY or THE INVENTION EMBODIMENTS This invention isnovel compounds of the formula: The invention is novel esters of(film/nylon)" kenyloxy)-, and (cyanoalkoxy) carbanilic acid sand theiruse for controllingundesirable vegetation. These X esters can beprepared by several procedures. N 9 To a mor p-hydroxycarbanilate ester(II below) in ,C a solvent such as acetone, alcohol (e.g. ethanol or E 1methanol), DMF, etc., is added a molar equivalent of a base such asanhydrous sodium carbonate, potassium A carbonate, potassiumhydroxide,sodium hydroxide, sodium alkoxide (e.g. methoxide), potassiumt-butoxide, wherem A 15 hydrogen, halogen y butyl lithium ortriethylamine'. To the stirred mixture (Cl-C4) alkoxy monohaloalkyl(C1-C5), dlhar the alkynyl halide (l to 2 moles) is added dropwiseloalkyl (C1"C4) trlhaloallkyl (Cr- 4), IIIU'O or with stirring. Thereaction temperature range is from 0 )n 0, 1 0T B ls 40 to 100C, but 56to 65C. is generally preferably.

After reaction for several hours l to 60 hours), the B5 mixture ispoured onto ice-water containing sodium carbonate or sodium acetate. Asolid usually separates f and in filtered off and crystallized. In someinstances, 4 it may be necessary to chloroform extract the solution andevaporate to a residual oil, followed by crystalliza- X and Y am xygSulfur; 1 18 y g o lkyl tion. The reaction may be graphicallyillustrated as fol- (C -C R is straight or branched alkyl (C C, cy-.lows:

i i H N-CX-YR; Cl-(|)-C C-lt II III 5 I RV, -G=C-f-O v i v-cx-r ricloulkyl (C 0). heniyl, chlorobenzyl. methylbenzyl. phcnyl.chlorophcnyl, mclhylphenyl, alkenyl (C -C monohaloalkenyl (C -C alkynyl(C -C monohaloalkynyl (C -C monomethoxyalkynyl (C -C R and R arehydrogen or methyl; R is -CN,

-o on; 151 b.; o e R6 R is hydrogen, methyl or halogen, and R ishydrogen, alkyl (C,C alkoxyalkyl (C -C haloalkyl (C 41 or halogen;provided that the members represented by A and B are respectivelyattached to the carbons in the ring which are metaand parato the carbonattached to the nitrogen, or they are respectively paraand metato thering carbon attached to the nitrogen, and

where R,, R R R R and A are as defined above. This reaction is alsouseful for the preparation of the alkenyloxyand cyanoalkoxycarbanilicacid esters (substituting allylic chlorides and the thiono and dithioderivatives thereof.

Alternatively, the (alkynyloxy)aniline (IV) is either reacted directlywith a chloroformat'e' ester (V) in an aprotic solvent (e.g. CH CN, DMF,acetone, THF) COCl Treatment of a solution of (alkynyloxy)aniline (IV)in an aprotic solvent (ethyl acetate preferred) with an excess ofphosgene, usually at reflux temperature affords the isocyanate (VI).Addition to the appropriate alcohol (R OH), usually at 50 to 60C.,affords the carbamate (I).

In a similar manner, the intermediate m-or phydroxycarbanilate (II)ester is prepared from the appropriately substituted m-or P-aminophenol(VII) by either the agency of an alkyl chloroformate or preferablyphosgene and an alcohol (R OH). The ease of the latter route issurprising since hydroxyphenylisocyanates are known to polymerizereadily. However, the reaction with alcohols (R OH) is rapid, especiallyso 15 with primary and secondary alcohols. (Table I below describesyields by procedures 1 or 2).

2 no N=C=0 H0 NR -CO-CI Procedure 1 HO Nil-R 03 VII - Procedure 2 HO NRCO H c1 c R2 l 2 E L containing a base acceptor (ether sodiumbicarbonate or sodium carbonate as suspensions or triethylamine orpyridine). After reaction, usually at room temperature, the reactionmixture is poured onto ice-water contain- The compounds of the inventionare readily soluble in many common organic solvents such as alcohols(e.g. metanol, ethanol, and isopropanol), ketones (e.g. acetone,methylethylketone, and cyclohexanone), and

ing 1N hydrochloric acid. The product separates out 45 aro atic hy r carn (e-gtoluene, and yand is filtered off, dried and crystallized.

lene). This solubility characteristic is a significant ad- I i N-com R,OH

I" N-CO-C1 ClCOgRg (V) B aura, B A d A (A and Bag previously defined)N.=C=O or B vantage in formulating the compounds for use in thefieldsince it permits preparation of a wide variety of liquid and solidformulations by relatively simple techniques. Emulsifiable concentratescan be prepared by dissolving from about percent to 85 percent by weightof the active compound in an organic solvent or mixture of organicsolvents (eg those mentioned above), and admixing with the thus-formedsolution from about 1 percent to 10 percent by weight of an emulsifieror mixture of emulsifiers. Among the emulsifiers which can be used areanionic-nonionic blends generally made up of oil soluble sulfonatecalcium, or

. amine salts and polyoxyethylene ethers.

Wettable powders can be prepared by dissolving from about 10 percent to85 percent by weight of the active compound in a lower alcohol (C -Cketone (C -C toluene, xylene, benzene, or the like, and spraying thethusprepared solution on a finely ground inert diluent such asattapulgite, kaolin, diatomaceous earth, talc, silica, pumice, or thelike. Generally, about 1 to 10 percent by weight of a dispersing agent(e.g. sodium lignosulfonat'e or monocalcium salt of a polymerizedalkylaryl sulfonic acid), and from 1 to 5 percentby weight of a wettingaagent or surfactant (elg. polyoxyethylated vegetable oil, alkylphenoxypolyoxyethylene ethanol, sodium alkylnaphthalene sulfonate, or ester ofsodium isothionate). are a;sp added to the formulation.

In practice, the wettable powder or emulsifiable con centrate isgenerally dispersed in water and applied as a liquid spray to thefoliage of undesirable plants or to soil containing seeds of undesirableplants. The spray is generally applied in sufficient amount to provideabout 0.2 pound to pounds of active compound per acre of treated area.For selective control of broadleaf weeds and grasses in the presence ofagronomic crops, usually only about *0.2 pound to 4 pounds of activecompound per acre of treated area is required.

Where desired. the compounds of this invention may also be formulated asdusts, dust concentrates and granular formulations using conventionalpractices.

Thisinvention is further illustrated by the examples set forth below.

EXAMPLES l and 2 Preparation of mand p-Hydroxycarbanilic Acid Esters4-Hydroxycarbanilic Acid, Methyl Ester by Prodedure Methylchloroformate(48 grams, 0.5 mole) is added dropwise to a cooled (0C. to 10C.) stirredmixture of p-aminopheno1 (54.6 grams, 0.5 mole) and sodium bicarbonate(42 grams) in DMF (250 ml.). The mixture 5 is allowed to attain 25C.after 3 hours and a few drops of pyridine are added. After a furtherhour, the mixture is filtered and evaporated to a residual oil, which isstirred and scratched with 2N hydrochloric acid to give a solid. Thesolid is filtered off and crystallized from benzene to give 31.2 grams,37 percent, melting point 113.5 to 114.5C. or: Procedure 1HO-Q-NH-CO-OCH,

solution (0.25 mole) is added rapidly to methanol- 1800 ml.). Then afterone hour the mixture is warmed to reflux for 16 hours. The solvent isremoved under reduced pressure, and the residue is crystallized frombenzene to give the product, melting point 112 to 113.5C., 26.7 grams,65 percent.

EXAMPLE 3 PREPARATION OF 3-CHLORO-4-HYDROXYCARBAN1L1C ACID,

METHYL ESTER BY PROCEDURE 1 cigoa Powdered 4-amino-2-chlorophenol (210grams, 1.46 moles) is added to a dry ethylacetate solution (2100 ml.)ofphosgene (210 grams, 2.05 moles) and the mixture is stirred at 0 to10C. Slowly the reaction mixture is raised to reflux temperature after 1hour. Further phosgene (20 grams) is passed through the solution duringa VA hour period, then the mixture is heated to 40C., and rapidlyfiltered. The filtrate is evaporated under reduced pressure to a volumeof 900 ml. An infrared spectrum of this oil has a peak at 2260 cm.(N=CO). The isocyanate solution is added to methanol (1.8 liters) withstirring, and the reaction is brought to reflux for 16 hours, then setaside at 20C. for 48 hours. Evaporation of the reaction mixture affordsa under reflux during another 30 minute period, cooled viscous oil.Addition of benzene (2 X 300 ml.) followed To a solution of4-amino-2-chlorophenol (21.45 by evaporation causes the oil to solidify.The crude grams, 0.15 mole) in dry DMF (150 ml.) and pyridine solid isvacuum dried, melting point 96 to 98C., 250.5 grams (86 percent).Crystallization of a 5 gram sample (1 1.8 grams) is added at C. slowlydropwise with stirring isopropyl chloroformate (16.5 grams, 0.016

from benzene (trace n-hexane) affords crystals, meltmole). After 4 hoursat 0 to 5C., a further one gram ing point l04 to 105C, 2.76 grams (47percent).

of isopropyl chlooroformate is added. The mixture is stirred at 25C. for16 hours, then poured into icedilute hydrochloric acid. After 4 hoursstirring and EXAMPLES 4 THROUGH 9 scratching, a solid separates out andis filtered off. (PROCEDURE AS EXAMPLE 1) 10 Crystallization frommethanol gives 14.5 grams, 42 percent, melting point 89 to 90C.PREPARATION OF 3-CI-ILORO-4-I-IYDROXYCARBANILIC ACID,

Following the procedure of Examples 1 or 2 above, but utilizing theappropriate phenol and chloroformate. or appropriate alcohol andphosgene in the reaction,

yields the compounds listed below in Table l.

ISOPROPYL ESTER AND DERIVATIVES -c1 A HO-Q-NH-COOCMCH, 1 1

H mm .5355 27min m N: ocomcoo, H ocmxos ocomcwn H OH wcowcwn H mmmcmxwso oho osms ou m i mnswooopm w co pm gmpmzpo w M u H w ucwom 3 2 HmAmEB m0 28-93 E S EQ f S m o oo mzgom HI m 8 m N3 mob 8:2 .om

upsuosppm w Ho 6951 Yom om i mo domzi v om 2 mow mo GO ETA Yom 3 2 H mm3 03 62 mo ao mz g om 3 H R @83 midi A #65 do mz g om 3 mksnmoonm mma nomn n mpm .Ho 0 mmnposnpw .v nmnfisz ww mo uqmk om pqwom mamflmunm 7EXAMPLE 21 PREPARATION OF 3-CHLORO-4-(2-PROPYNYLOXY)CARBANILIC Propargylbromide (1.79 grams, 0.015 mole) is added dropwise to a stirred mixtureof the isopropyl ester of 3-ch10r0-4-(hydroxy)carbanilic acid (3.45

grams, 0.015 mole), and anhydrous potassium carbon- ACID, ISOPROPYLESTER i EXAMPLE 22 Following the procedure of Example 21 andsubstituting the appropriate carbanilic acid ester for the isopropylester of3-chloro-4-(hydroxy)carbanilic acid and the appropriate alkenylhalide, alkynyl halide or cyanoalkyl halide for prop'argyl bromide,yields the compounds identified below in Table H.

HO Br-CH -C CH Propargyl bromide (130 grams, 1.1 moles) is added to amixture of the methyl ester of 3-chloro-4- hydroxyca'rbanilic acid (213grams, 1.06 moles) and anhydrous potassium carbonate (152 grams, 1.1moles) in dry acetone (2.5 liters), and the mixture stirred and heatedunder reflux during 21 hours, cooled and poured into ice watercontaining 5 percent sodium carbonate. A solid separates out and isfiltered off and air dried to give 250 grams,-99 percent, melting point124 to 124.5C. Crystallization from benzene/hexane gives pureproduct,melting point 126 to 126.5C., 173 grams (69 percent). Infrared andnuclear magnetic resonance are superimposable with the product preparedby other procedures.

EXAMPLE 24 PREPARATION OF 3-CHLORO-4-(Z-(PROPYNYLOXY)CARBANILIC ACID,METHYL ESTER HO- l\lHCON(CH I Na CO HC C-CH O- 2 NHCO-OCH action mixtureat a rate sufficient to maintain the temperature at reflux. After theaddition is complete, the mixture is refluxed for an additional 9 /2hours.

The reaction is then cooled and poured into ice and water containing 1percent of sodium carbonate. After about 15 minutes, a precipitateforms. However, the mixture is stirred for an additional hour, thenfiltered, Washed, and dried.

The crude material from above is passed through a dry silica gel columneluting with benzene. The product is located on the column, cut out andextracted with methanol. The methanol is then removed leaving anoff-white solid, melting point 120 to 122C., which is crystallized usingbenzene/hexane to white crystals having a melting point of 122.5 to123.5C. It is not certain if the methoxide displacent of dimethylamineto give this product occur s directly on the ureidophenol or on thepropargyloxyphenylurea or on both.

EXAMPLE 25 The selective postemergence herbicidal acitivity of thepreferred compounds of the present invention is demonstrated by thefollowing tests, wherein a variety of monocotyledonous anddicotyledonous plants are treated with test compounds dispersed inaqueous acetone mixtures. In the tests, seedling plants are grown inplastic pots for about 2 weeks. The test compounds are dispersed in50/50 acetone/water mixtures containing 0.5 percent v/v surfactant insuffieient quantity to provide the equivalent of about 0.19 to 10 poundsper acre of active compound when applied to the plants through a spraynozzle operating at 40 psi. for a predetermined time. After spraying,the plants are placed on greenhouse benches and are cared for in theusual manner, commensurate with conventional greenhouse practices. Twoweeks after treatment, the seedling plants are examined and ratedaccording to the rating ferred compounds are highly effective for thecontrol 7 MeOH Br-CH -C CH of undesirable broadleaf weeds and grasses.

The specificity of the compounds of the invention for control of weedsand grasses in the presence of rice is particularly well demonstrated bythese tests.

'Z Difference in (imwlh Rating System: from the Check" formation butwith an over-all effect less than a 5 on the rating scale.

Based on visual determination ofstand,

size. vigor, chlorosis, growth malformation and over-all plantappearance.

Plant Abbreviations:

SOY Soybean MG Morning-glory VE Velvefleaf CR Crabgrass RAG Ragweed RRice TO Tomato LA Lambsquaners GRF Green foxtail .MU Musiard W0 Wildoats PI Pigwced COR Corn BA Barnyard grass COT Cotton PlantAbbreviations:

w N O N m H m .0 m m m 3 N o o m a m n o w n w 3 N O m m m m N o m N w 3w m H m m m m o w w w 3 N. w m m m m w o m w m 3 H m m H o H N m N H m mw m 35 m m m N o m m m w m m m m m mm o w \i w w m m m m m N. m m m mmkfio m m N m m m m m m m m m m m m H m m m M. m N. m m m m m m m m m \im m w m w m m m m m m m m m m m Hmm a MM w m m m o m w H m g 3 moohomumwz amass, m pcwEummna HHH mdmqrw M m Q Q w HQQ mSmmQ o m o muummu moooo mz mhsuushum o muio om.

QPQE S HHH Sm:

Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q QQ Q H H Q Q QQ Q Q H Q Q H Q QH H Q Q N H Q Q Q Q Q Q Q Q Q Q mm H Q Q Q Q Q Q Q Q QQ Q Q Q Q QQQiQiQiZ QQQQQQMMQQ Q Q Q Q Q Q Q Q. Q Q Q QH Q Q m Q Q Q Q QQ Q Q Q Q Q Q QH QQQQQQ Q Q QQ QQQWQQ Q m v U Q i i Q Q Q Q Q Q Q Q Q QQ Q QH QQiQ mo 0 mQQumQ Q m mm m NW Hmm Q QQ Q mm QdeQ Qm QM m w z fi QNQ H gm wmo o mummz Hmong pcoEpmwL EXAMPLE 26 mixed with potting soiland planted on top of approxi- The selective preemergence herbicidalactivity of the 65 mately 1 inch of soil in separate 2-inch plasticpots.

compounds of the invention is exemplified by the fol After planting, thepots are sprayed with the selected lowing tests in which the seeds of avariety of monocotaqueous acetone solution containing test compound inyledonous and dicotyledonous plants are separately sufficient quantityto provide the equivalent of about y the comlittle or not 32 desirableplant species. The specificity of the compunds of the invention forweeds and' grasses in the presence of rice,

'31 0.38 to 10 pounds per acre of test compound per pot. The treatedpots are then placed on greenhouse benches and cared for in accordancewith greenhouse corn cotton and soybeans, is particuprocedures. Threeweeks after treatment, the tests are larly well demonstrated by thesetests. Note that many terminated and each pot is examined and ratedaccord- 5 broadleaf and grass weeds which are common to cor ing to therating system set forth in the preceding examcotton and rice culture arecontrolled b ple. The tabulated results'of these tests establish thesepounds described in this invention with lective herbicidal proficiencyof the test compounds, damage to the desired crop plants. Data obtainedare when properly applied, for controlling a variety of unreported inthe Table below.

0 O o O o a Q o o O o m e m e m N a m 0 or m m m m a w m m. 3 m 05%; 5o5 A Q m $6016 m N o o o m m m N m w w J m N m D m m e N m w m m S Edd eo m H o m o o O m m r m m N m w m e v N o o w m N m m m m w 3 mo o wlmcmomo mo o m 8 o O 0 H w o o O m e w J a o O o o m e m m m o m m. 3 T m oo wa $535 m o o o o o o N m m o m N o m wmd o t O o Q Q m m N c N m o mE5 .8 o e o o o o m m w H m m w m m4 0 N. o m o o N m m m m m m m m m mm m H m N. m m m m m m m m m mooloolmz o... moionum m n He m Mam m oo WMmu m o m DIE u j mhsuonpum mmono momma amaze ucoEumoh We claim: ItCompounds of the formula:

3. EQ'C-Y-R B R wherein A is hydrogemhaiogen, alkyl (C C";), alkoxy (C,C),'monohaloalkyl (C -C dihaloalkyl (C -C trihaloalkyl (C C or nitro; Bis R -c-O- 'X and Y are oiry ent R is hydrogen or alltyl (C 42 R isalkyl (C C cycloalkyl (C -C benzyl, chlorobenzyl, methylbenzyl, phenyl,chlorophenyl, methylphenyl, alkenyl (C -C monohaloalkenyl (C -C alkynyl(C 43 monohaloalkenyl (C -C alkynyl (C -C monohaloalkynyl (C C ormonomethoxyalkynyl (C -C R and r,, are hydrogen or methyl;

l Rli and R is hydrogenl halogen, ailryl (Cf-C alkoxyalkyl (C -C orhaloalkyl (C -C4) Provided that A and B are respectively attached to thecarbons in the ring which are metaand paraor paraand metato the carbonattached to the nitrogen; and provided that when B is CH =CHCH O-, X isoxygen.

2. A compound according to claim 1 wherein B is 3. A compound accordingto claim 2 wherein B is HCCCH -O; A is Cl; R is H; X and Y are and R isCH.

I 4. A compound according to claim 2 wherein B is HC CCH -.-O A is H; Ris H; X and Y are 0; and R2 is tert-C4H9.

5. A compound according to claim 2 wherein B is H2 er and R R and R areeach hydrogen or methyl.

6. A compound according to claim 2 wherein B is A is C]; R R are H; andY are 0; and R is methyl 7. A compound according to claim 2 wherein B isA is 3-Cl; R, is and Y are 0; and R is CH 8. A compound according toclaim 2 of the formula:

CHECCHZO 10. A compound according to claim 2 of the formula:

1. COMPOUND OF THE FORMULA:
 2. A compound according to claim 1 wherein Bis
 3. A compound according to claim 2 wherein B is HC*C-CH2-O-; A is Cl;R1 is H; X and Y are O; and R2 is CH1.
 4. A compound according to claim2 wherein B is HC*C-CH2-O-; A is H; R1 is H; X and Y are O; and R2 istert-C4H9-.
 5. A compound according to claim 2 wherein B is
 6. Acompound according to claim 2 wherein B is
 7. A compound according toclaim 2 wherein B is
 8. A compound according to claim 2 of the formula:9. A compound according to claim 2 of the formula:
 10. A compoundaccording to claim 2 of the formula: